Before selling your iPhone 5, sending to Apple, or otherwise sharing it, note the following: performing a "Restore" operation on the iPhone 5 does not delete personal data from the device. In fact, mail, contacts, and various other data remain intact on the device after a restore, then you should eraser all the data for iPhone 5.

File Types Supported to Erase on iPhone 5:
Contact, Message, Call History, Calendar, Email, Note, Reminder, iTunes DB, App (and generated data), System setting, Apple ID, Photo, Video, Voice memo, Keyboard Cache, Safari Bookmark, Passbook, and more

The iOS SafeEraser - iPhone Data Eraser, Wipe iPhone Remotely, Delete iPhone Data Before Selling
> Permanently erase content from your iPhone 5S/5C/5/4S/4
> Works with all iOS Devices - Jailbroken iPhone friendly and also compatible with carrier-locked iPhones

Related use guides:

How to Permanently Delete Photos from iPhone

How to Delete iPhone data permanently

Some facts mentioned above are incorrect but still I would say nice tutorial buddy! I would also like to recommend this iPhone data eraser software, which is designed to permanently erase data from iPhone, iPad and iPod. This program is far better than the other similar programs,I have ever use this iPhone data eraser software to delete contacts on iPhone permanently.

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